Cell Communication - Vocab

cell signaling

The molecular mechanisms that enable cells to respond to their environment are collectively

signaling pathway

Signaling molecules act on target cells by triggering a series of interactions between molecules

Reception

signaling molecule binds to a receptor protein by fitting into an appropriately shaped binding site

A molecule that binds to a receptor in this way is a

ligand

All of the interactions between molecules that are triggered by activation of a receptor, and lead to a cell’s response

signal transduction

enzymes that transfer a phosphate group from ATP to one or more specific amino acids on

target proteins

protein kinases

target proteins subtly changes their conformation. This change can activate or inactivate a target protein, depending on the particular protein and where it is phosphorylated.

Phosphorylation

Protein kinases often phosphorylate other protein kinases, producing a

phosphorylation cascade

The purpose of reception and transduction is to change the functioning of a target cell.

Response

cells recognize each other using direct contact communication, and cellular responses in these signaling pathways reinforce the attachments between cells.

cell–cell recognition

In animal cells, the direct channels of communication are ___ , specialized connections between the cytoplasms of adjacent cells

gap junctions,

In plant cells, the direct channels of communication are

plasmodesmata

aqueous fluid surrounding and between the cells.

extracellular fluid

A specialized type of paracrine signaling in animals takes place at

chemical synapses

molecules that diffuse across the chemical synapse and bind to receptors in the plasma membrane of the adjacent cell.

neurotransmitters

In some cases, the local regulator acts on the same cell that produces it, a process called

autocrine regulation

form of communication, one cell secretes a long-distance signaling molecule called; which produces a response in target cells that may be far from the hormone-secreting cell

hormone

(hormaein= to excite)